CODEWITHSUNDEEP
phppreg-replace
kylex
kylex

Reputation: 14406

preg_replace() remove all non-numeric characters EXCEPT trailing x

I have the following code to remove all non-numeric characters:

$num = preg_replace('/\D/', '', $num);

I'd like to make it so that it removes all numeric-characters except any trailing X (not case sensitive).

ex:

s34kr = 34

xX4rx = 4x

rs5t928X = 5928X

Upvotes: 2

Views: 1736

Answers (2)

Sswater Shi
Sswater Shi

Reputation: 189

Try:

$num = preg_replace('/(?:(?!\b\d+[xX]?\b).)*(\b\d+[xX]?\b)?/', '$1', $num);

Upvotes: 0

Ja͢ck
Ja͢ck

Reputation: 173662

You could use look-ahead assertions, coupled with an alternation like this:

preg_replace('/\D(?=.)|[^xX]$/', '', $num);

It matches a non-digit only if followed by another character or a trailing character that's not 'x'.

Alternative

You could consider matching instead:

if (preg_match_all('/\d+|[xX]$/', $num, $matches)) {
     $num = join('', $matches[0]);
} else {
     $num = '';
}

This matches any number of digits or trailing 'x' and then joins the captured matches together.

Upvotes: 1

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